RNS Number:3198U
Marconi Corporation PLC
16 January 2004


Wanger Asset Management, L.P.
227 West Monroe, Suite 3000
Chicago, Illinois 60606
Tel: (312) 634-9200



BY UPS NEXT DAY AIR


January 14, 2004



Marconi Corp PLC
Attention: Company Secretary
34 Grosvenor Square
London, W1A 4QP
United Kingdom



Ladies and Gentlemen:



We hereby notify you in fulfilment of the obligation of disclosure imposed by
the provisions of Sections 198 to 202 of the Companies Act (1985) (the "Act"),
that:


(a) Liberty Wanger Asset Management, L.P. has recently decreased their
position in Marconi Corp PLC (the "Relevant Shares") from 3.6% to 0.7% of the
companies outstanding shares.  Liberty Wanger Asset Management recently sold
5,755,000 shares and now holds 1,455,000 shares in Marconi Corp PLC which
represents 0.7% of the companies outstanding shares of 200,002,000 shares.



(b) The registered holders of the Relevant Shares are:



Wanger Advisors Trust Foreign Forty Fund - State Street Nominees Ltd. 27,500
shares

Liberty Acorn International Fund-State Street Nominees Ltd. 1,075,000 shares

Liberty Acorn Foreign Forty Fund-State Street Nominees Ltd. 54,000 shares

AXP Partners International Aggressive Growth Fund - Bank of New York 60,180
shares

Wanger European Small Cap Fund - State Street Nominees Ltd. 238,320 shares



(c) Liberty Wanger Asset Management, L.P. is interested in the Relevant
Shares by virtue of Section 208 (4)(b) of the Act; and



(d) This notification is given on behalf of Liberty Wanger Asset Management,
L.P. and its registered address at 227 W. Monroe Street, 30th Floor, Chicago,
Illinois 60606.



Yours faithfully,



Liberty Wanger Asset Management, L.P.
By WAM Acquisition GP, its general partner



Bruce H. Lauer
Senior Vice President and Secretary




                      This information is provided by RNS
            The company news service from the London Stock Exchange
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